External Tank

OverviewWanda Sigur

External Tank

OverviewWanda Sigur

The Space Transportation System (STS)The Space Transportation System (STS)

External TankExternal TankLockheed MartinLockheed Martin

Main EnginesMain EnginesBoeing (Rocketdyne)Boeing (Rocketdyne)

OrbiterOrbiterBoeing (Rockwell)Boeing (Rockwell)

Solid Rocket BoostersSolid Rocket BoostersAlliant Techsystems (Thiokol)Alliant Techsystems (Thiokol)

The External TankThe External Tank

Length = 153.8 Feet; Diameter = 27.6 FeetLength = 153.8 Feet; Diameter = 27.6 Feet

Liquid Oxygen TankLiquid Oxygen Tank• 1,385,000 lbs. / 145,138 gals. Oxidizer • - 297 Degrees Fahrenheit• 1,385,000 lbs. / 145,138 gals. Oxidizer • - 297 Degrees Fahrenheit

Liquid Hydrogen TankLiquid Hydrogen Tank• 231,000 lbs. / 309,139 gals. Fuel• - 423 Degrees Fahrenheit• 231,000 lbs. / 309,139 gals. Fuel• - 423 Degrees Fahrenheit

IntertankIntertank• Unpressurized

Structure• Unpressurized

Structure

Aft ET / OrbiterInterface(2 places)

Aft ET / OrbiterAft ET / OrbiterInterfaceInterface(2 places)(2 places)

ForwardET / Orbiter InterfaceForwardForwardET / Orbiter InterfaceET / Orbiter Interface

External Tank External Tank Structural InterfacesStructural Interfaces

ET / SRB Forward ThrustAttach Fittings (2 places)ET / SRB Forward ThrustET / SRB Forward ThrustAttach Fittings (2 places)Attach Fittings (2 places)

ET / Ground InterfaceGround Umbilical PlateET / Ground InterfaceET / Ground InterfaceGround Umbilical PlateGround Umbilical Plate

ET / SRB Aft Attach fittings3 each (2 places)

ET / SRB Aft ET / SRB Aft Attach fittingsAttach fittings3 each (2 places)3 each (2 places)

ET Production HistoryET Production HistoryET Production History• 121 Units Delivered to Date• Three Versions• 121 Units Delivered to Date• Three Versions

• Lightweight Tank• Lightweight Tank

• Super Lightweight Tank• Super Lightweight Tank

– Al 2219 (Al = Aluminum)– Dry Wt. 77,099 lbs. – Al 2219 (Al = Aluminum)– Dry Wt. 77,099 lbs.

• Standard Weight Tank• Standard Weight Tank

– Al 2219– Dry Wt. 65,767 lbs.– Al 2219– Dry Wt. 65,767 lbs.

– Al 2195 (Al-Li = Aluminum Lithium) – Dry Wt. 58,319 lbs.– Al 2195 (Al-Li = Aluminum Lithium) – Dry Wt. 58,319 lbs.

66

8787

2828

66

8686

2121

DeliveredDeliveredDelivered FlownFlownFlown

(1981 - 83)(1981 - 83)

(1983 - 98, 2002, 2003)

(1983 - 98, 2002, 2003)

(1998 - present)(1998 - present)

(actual ET1)(actual ET1)

(actual ET71)(actual ET71)

(actual ET96)(actual ET96)

• Substantially Completed Tanks• Substantially Completed Tanks 44

19731973 19741974 19751975 19761976 19771977 19781978 19791979 19801980 19811981 19821982 19831983 19841984 19891989 19901990 19911991 19921992 19931993 19941994 19951995 19961996 1999199919851985 19861986 19871987 19881988 19971997 19981998 20002000 20012001 20022002 20032003 20042004 20052005 20062006 20072007 2009200920082008

ET Production HistoryET Production History

Standard Standard Weight Weight TankTank

Lightweight TankLightweight TankSuper Super

Light Light Weight Weight

TankTank

RTF RTF TankTank

Since the Shuttle Program began, the ET has successfully undergone several redesigns to meet the changing needs

of our Nation’s space program

Since the Shuttle Program began, the ET has successfully undergone several redesigns to meet the changing needs redesigns to meet the changing needs

of our Nation’s space program of our Nation’s space program